Four-years crossing scheme involving Spanish V-line (V) and Egyptian Baladi Red (B) rabbits was practiced to produce five genetic groups of V, B, ½B½V, (½B½V)2 , and ((½B½V)2)2 . A new line with a genetic structure of ((½B½V)2)2 was synthesized and named APRI. A total of 2834 litters produced from 848 does pedigreed by 477 dams and 272 sires were used to evaluate litter size at birth (LSB) and weaning (LSW), litter weight at birth (LWB) and weaning (LWW), and pre-weaning litter gain (PLG). A generalized least square procedure (GLS) was used to estimate direct additive, direct heterosis, maternal heterosis, and direct recombination effect. Heritabilities for litter traits were mostly low and ranging from 0.01 to 0.18, while the permanent
environmental effects were mostly moderate and ranged from 0.09 to 0.33. Direct additive effects were mostly in favour of V-line does; indicating significant effects only for LSB and LWB by 23.0% and 24.2%, respectively, relative to the average of the means of V and B. All estimates for direct heterosis were significant and ranging from 20.0 to 27.7 %. The magnitudes of the estimates of maternal heterosis were mostly opposite to the magnitude of direct heterosis since the estimates were negatively unfavourable; ranging from -10.0 to 12.3 % comparing to the founder breeds.
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